The study of drought factors to analyze and manage water is very important. The main contributing factor to drought is unusual summer weather wind pressure and air mixtures include water vapor and water droplets. In this factors can be analyzed for rainfall in the lower central river basin area and the preliminary data of the research used to analyze drought from Thai Meteorological Department (TMD). This research analyzes the factors that cause drought including rainfall temperature pressure wind and precipitation. The Multiple linear regression analysis used to determine the relationship of factors causing drought. It was found that rainfall had a statistically significant relationship with temperature and pressure. In addition using the Geographic Information System (GIS) an analysis of rainfall in the lower central river basin from October 1920 to September 2021 to found that from August to October there is a lot of heavy rainfall according to the multiple linear regression equation. Therefore the created multiple linear regression equations can be effectively used in the analysis of drought areas in the lower central river basin area.

This research is a qualitative research. Aim to study how to handle an effective water management. Case study: Muang Samutsakorn District Samutsakorn Province. Either before implementation or during the process and post implementation after the project has been achieved. Sampling groups are agencies involved representing the effective water management resulting in helping Muang Samutsakorn Samutsakorn Province survived from the B.E.2554 mega flood crisis. Consist of Director Head of Engineering Water Delivery and Maintenance Project Phasi Charoen Irrigation Office 11. The research results are summarized below. 1. Pre-implementation Preparation by dredging various gutter in the canals removing all water obstacles installing more mobile water pumps at main pumping stations. Establishing working committee for flood solving and preventing Center. Furthermore check the readiness of tools to be used. 2. During the process Start running the operation center to solve the crisis and closely supervise the action plans. Co-ordinate between Nakhon Pathom Province Samutsakorn Province Bangkok Metropolitan Administration and Department of irrigation in administration of water management. Integrate all parties concerned like government and private sectors. 3. Post-implementation Continuously publicize the outcome. Repair the sewage and drainage system which are damaged from use. Make further sustainable plan for drainage system.